This invention relates to a terminal-cover assembly for use in a sealed electrical component package and more particularly to a metal cover having an insulated through terminal mounted therein for use in a hermetically sealed electrolytic capacitor package.
Although many terminal-cover assemblies are known for use in hermetically sealed electrolytic capacitor packages, most of them, and particularly the multi-terminal type, employ a phenolic, plastic or otherwise non-metal cover material. Metal covers are more readily sealed to a metal can by reliable sealing means such as tungsten inert gas welding, ultrsonic welding, brazing and the like. Metal covers and cans are stronger and usually less bulky for withstanding physical stresses of handling, mounting or internal pressures often generated by operating electrolytic capacitors contained therein. Metal cans are often preferable for serving as a cathode electrode in electrolytic capacitor packages. Capacitor anodes of aluminum are preferably packaged in aluminum cans which are compatible to and inert to the electrolyte solution being employed.
The stronger metal covers also are more readily adapted for making both the electrical and mechanical connection between the package and the package environment.
It is common practice in terminal-metal-cover assemblies to employ a glass insulating bushing about the terminals, representing an efficient but comparatively expensive assembly. It is also known to force fit a resilient bushing into an extruded and funneled opening in a metal cover, the terminal being compressed thereby in a center hole of the compressed bushing.
It is an object of the present invention to provide a terminal-cover assembly having a strong insulating bushing containing a metal terminal, the bushing being highly compressed within a hole in a metal cover.
It is a further object of this invention to provide a terminal-cover assembly for use in a hermetically sealed electrolytic capacitor package that is chemically inert to strong electrolytes, capable of withstanding large internal pressures without leaking electrolyte.
It is a further object of this invention to provide a method for making a low cost terminal-metal-cover assembly for use in a hermetically sealed electrolytic capacitor package.